1. Department of Mathematics, Govt. Gordon Postgraduate College Rawalpindi, Pakistan
2. Department of Mathematics, York Campus, Pennsylvania State University, York, PA 17403, USA
3. Department of Mathematics, University of Okara, Okara, Pakistan
4. Department of Mathematics, University of Sargodha, Sargodha 40100, Pakistan
5. Department of Mechanical Engineering, College of Engineering, Jazan University, P. O. Box 45124, Jazan, Kingdom of Saudi Arabia
6. Department of Mathematics and Statistics, RIPHAH International University Islamabad, Pakistan